The biggest risk are true white elephant projects. But if we delay every project for 5 years of review to avoid the chance of a white elephant, how many projects are we missing out on, how much extra are we spending to finance all that process?
The waste projects, as long as we can screen for show stoppingly bad projects which should be pretty obvious with cursory (but still detailed) analysis, might end up 'paying for themselves'.
Our processes are set up to avoid things like the Don Getty stimulus and diversification projects, things like the BC Fast Ferries. The thing is, analysis was they were wastes even then. We just slowed things down enough to try to let lack of enthusiasm kill them, not bad economics. The economics were always bad.
As long as there is someone sane at the wheel, what is the worst that can happen? Too much new housing? Too much optionality for exporting Alberta's oil? Too much rail export capacity? Are we going to be mad about some waste/subsidy of those things? Given what we've experienced over the last 20 years and the USA turning into an unreliable partner?